Rock or Stone Mineral Wool

Composition

Stone mineral wool is primarily made from volcanic rock, typically basalt or dolomite, or a combination of the two.

Increasing a significant proportion is now recycled material from slag, a waste product from blast furnaces. The materials are melted and then spun into fine fibres.

A resin is used to bind the fibres together to form a mat of insulation.

Characteristics

Short fibre - compressive strength

Suitable for temperatures up to 850°C Non-combustible

Denser than glass mineral wool

Available in the form of slabs, rolls and mattresses

High compressive strength

Main uses

Thermal insulation of ...

pitched roofs, flat roofs, and ceilings

external wall thermal insulation

interior wall thermal and acoustic insulation

sound insulation for floors and walls

rainscreen façades

Fire protection, including smoke and fire barriers

High temperature applications

Insulation Slabs, Batts, and Rolls

These insulation products resist the transfer of heat, by relying on pockets of trapped air or gas within its structure and its thermal resistance is consistent regardless of the direction of heat flow through it.

They include materials such as glass and stone mineral wool, cellulose fibre, and rigid plastic insulation boards.

All of these products have a specific thermal resistance for a given thickness of material at a given temperature.

 

Glass Mineral Wool

Glass mineral wool is made from sand and recycled glass, limestone and soda ash.

These are the same ingredients that are used to make familiar glass objects such as window panes or glass bottles.

The glass is spun to form millions of fine fibres.

A resin is used to bind the fibres together to form a mat of material.

Characteristics

Long fibre, giving good tear strength

Suitable for temperatures up to 230°C

Non-combustible

Lightweight

Available in rolls and slabs

Main uses

Loft Insulation

Cavity wall insulation

Sound insulation (absorption) within partitions and floors

Which to choose, Rock or Roll?

The density of the product determines whether the insulation is a lightweight quilt supplied in rolls, a flexible slab or a rigid slab, and it’s thermal insulation value.

Being rigid or semi rigid, slabs have the advantage of better thermal and acoustic values; firmness; strength; and density.

Insulation rolls are easily and quickly installed, and offer flexibility when there are pipes and wiring between rafters and joists.

 

Manufacturers that we predominantly support

Knauf Insulation Ltd, PO Box 10, Stafford Road, St Helens, Merseyside, WA10 3NS
Technical Advisory Tel: 01744 766666 Fax: 01744 766667 Email: tech@knaufinsulation.com

Rockwool Limited, Pencoed, Bridgend, South Wales, CF35 6NY United Kingdom
Tel: 01656 862621 - Fax: 01656 862302 - Email: info@rockwool.co.uk

Page updated November 10, 2008